Laser eye surgery systems have become ubiquitous and varied in purpose. For example, a laser eye surgery system may be configured to reshape the anterior surface of the cornea via ablation to effect a refractive correction.
A laser eye surgery system may also be configured to create a corneal flap to expose an underlying portion of the cornea such that the underlying portion can be reshaped via ablation and then recovered with the flap. More recently-developed laser eye surgery systems may be configured to create one or more incisions in the cornea or limbus to reshape the cornea, create one or more incisions in the cornea to provide access for a cataract surgical instrument and/or to provide access for implantation of an intraocular lens, incise a capsulotomy in the anterior lens capsule to provide access for removal of a cataractous lens, segment a cataractous lens, and/or incise a capsulotomy in the posterior lens capsule opening.
Many laser eye surgery systems generate a series of laser beam pulses via a laser beam source. The laser beam pulses propagate along an optical path to the patient's eye. The optical path typically includes controllable elements such as scanning mechanisms and/or focusing mechanisms to control the direction and/or location of the emitted laser beam pulses relative to the patient.
Some laser eye surgery systems are configured to track eye movement (e.g., change of viewing direction of the eye) such that control over the direction and/or location of the emitted laser beam pulses can be accomplished so as to account for the eye movement. For example, a laser eye surgery system may optically track a feature in the eye, such as a natural feature or a fiduciary marker added to the eye, so as to track movement of the eye.
In contrast, other laser eye surgery systems may be configured to inhibit eye movement. For example, a contact lens may be employed that directly contacts the anterior surface of the cornea so as to restrain eye movement. Such restraint, however, may cause associated patient discomfort and/or anxiety.
Beyond eye movement, many laser eye surgery systems are configured to inhibit relative movement between the patient and the laser eye surgery system. For example, a laser eye surgery system may include some sort of substantial patient restraint feature such as a dedicated support assembly (e.g., chair or bed), which can include restraint features configured to inhibit movement of the patient relative to the support assembly. Such a dedicated support assembly may include a positioning mechanism by which the patient can be moved to suitably position the patient's eye relative to the optical path of the laser eye surgery system. Additionally, a laser eye surgery system may be configured to rigidly support components that determine the location of the optical path of the laser pulses so as to substantially prevent movement of the optical path relative to the dedicated support assembly, thereby also inhibiting relative movement of the patient's eye relative to the emitted laser pulses. A dedicated support assembly and rigid support of optical path components, however, can add significant complexity and related cost to a laser eye surgery system. Additionally, the use of rigid support of optical path components and a dedicated patient support assembly can fail to preclude the possibility of some level of significant relative movement between the patient and the laser eye surgery system.
Thus, laser surgery systems with improved characteristics with respect to patient movement, and related methods, may be beneficial.